Golisano, who is retired, is the founder of Paychex Inc. and formerly owned the Buffalo Sabres.

He might not quite be out of the sports world, though: He recently confirmed he's been considering buying the Buffalo Bills to keep the team in-state.

Seles won the Grand Slam nine times, eight of them before she turned 20 years old. She entered the Tennis Hall of Fame in 2009. Her career was derailed in 1993 for two years after someone stabbed her in the back during a tournament in Germany.

As news of the engagement trickled into the media, comments about the romance popped up online.